BACKGROUND Elevated follicle stimulating hormone (FSH) is associated with poor vaginal oocyte retrieval (VOR) outcomes and cycle cancellations but intercycle variability in basal FSH reportedly does not predict ovarian response. METHODS We conducted a retrospective cohort study of basal FSH (n = 15573 cycles) in couples (n = 9132) who initiated IVF cycle(s) with basal estradiol (E2) <100 pg/m...

In order to elucidate the presence of free FSH-beta and LH-beta and their relation to the native hormones, immunoreactive FSH (IR-FSH), IR-LH, IR-FSH-beta, and IR-LH-beta subunits in the rat anterior pituitary and serum from 1200hr of proestrous day to 0600hr of estrous day were measured by radioimmunoassay. The amounts of IR-FSH-beta found were always more than those explained by the cross-rea...

Glycoprotein hormone receptors contain a large extracellular domain that is encoded by multiple exons, facilitating the possibility of expressing alternatively spliced transcripts. We have cloned two new splice variants of the rat follicle-stimulating hormone (FSH) receptor gene: FSH-R1 and FSH-R2. The splice variant FSH-R1 differs from the full-length FSH receptor mRNA by the inclusion of a sm...

The regulation by FSH (follitropin; follicle-stimulating hormone) of FSH receptor mRNA and protein (FSH binding) was studied using cultured Sertoli cells isolated from 21-day-old rats. FSH induced a dose-dependent and almost complete down-regulation of receptor mRNA at 4 h after addition of the hormone. At subsequent time points (16 h and later) the FSH receptor mRNA levels had returned close t...

The study aimed to investigate the effects of FSH and eCG on the ovarian and follicular development, expression levels of FSHR and caspase-9 of ovaries in vivo. One hundred and five prepuberty mice were allocated into FSH-1, FSH-2, FSH-3, eCG-1, eCG-2, eCG-3 groups and control group (CG). Mice in FSH-1, FSH-2 and FSH-3 were intramuscularly injected with 5, 10 and 20 IU FSH twice (on day 0 and 4...

BACKGROUND Adding clomiphene citrate (CC) to FSH for controlled ovarian stimulation (COS) decreases FSH dose required for optimum stimulation. However, because of its anti-estrogenic effects, CC may be associated with lower pregnancy rates offsetting the FSH-dose reduction benefit. Previously, we reported the success of aromatase inhibition in inducing ovulation without antiestrogenic effects. ...